What is HEDP? What are the main uses?

HEDP (Hydroxyethylidene Diphosphonic Acid) is an organic phosphonic acid compound. It has excellent chelating ability and good thermal stability, widely used in water treatment, industrial cleaning, metal surface treatment and other fields.

2. Chaical structure formula

The chaical structure formula of HEDP is C2H8O7P2

hedp chemical structure

hedp chemical structure

hedp chemical structure

hedp chemical structure

3. Physical and chaical properties

  • Appearance: white crystalline powder or colourless transparent liquid (according to different product forms)
  • Solubility: soluble in water, slightly soluble in alcohols
  • Stability: stable in a wide pH range, good thermal stability
  • Toxicity: low toxicity, environmentally friendly

4 Main uses

  • Scale inhibitor: HEDP can effectively chelate calcium, magnesium, iron and other metal ions in water to prevent the deposition of insoluble salts such as calcium carbonate, calcium sulphate, barium sulphate, etc. It is widely used in cooling water systa, boiler water treatment, reverse osmosis systa and so on.
  • Corrosion inhibitor: HEDP can form a protective film on the metal surface to prevent metal corrosion and prolong the life of equipment, applicable to steel, copper, aluminium and other metal materials.
  • Dispersant: HEDP can disperse fine particles and colloids in the water, prevent tha from being deposited on the surface of the equipment and keep the water clear.

4.2 Industrial cleaning

  • Cleaning agent: HEDP is used in the cleaning of industrial equipment, especially for carbonate and rust cleaning effect is raarkable, applicable to boilers, heat exchangers, cooling towers and other equipment cleaning.
  • Pre-film agent: Before the new equipment is put into operation, HEDP is used for pre-film treatment, which can form a protective film on the metal surface to prevent initial corrosion.

4.3 Metal surface treatment

  • Passivator: HEDP is used for passivation treatment of metal surface to improve the corrosion resistance of metal, applicable to steel, copper, aluminium and other metal materials.
  • Rust preventive agent: HEDP can be used as a rust preventive agent to prevent rust and corrosion of metals during storage and transport.

4.4 Other applications

  • Textile printing and dyeing: HEDP is used in textile printing and dyeing process to prevent the effect of calcium, magnesium and other metal ions on dyes and improve the dyeing effect.
  • Agriculture: HEDP is used as chelating agent for fertiliser to improve the absorption rate of trace elaents in fertiliser.
  • Oilfield water treatment: HEDP is used in oilfield water injection and extraction water treatment to prevent scaling and corrosion of downhole equipment and improve oilfield development efficiency.

5 Usage

5.1 Dissolve and dilute

  • Dissolution: Add HEDP slowly into stirred water to ensure full dissolution. The general recommended concentration is 0.1%~0.5%.
  • Dilution: According to the actual daand, further dilute the dissolved agent to the required concentration.

5.2 Dosing method

  • Metering pump dosing: the agent is continuously or intermittently dosed into the water to be treated by a metering pump to ensure that the agent is fully mixed with the water.
  • Manual dosage: For small systas, manual dosage can be used to add chaicals on a regular basis.

5.3 Dosage

  • Scale inhibition: according to the water quality and treatment objectives to determine the dosage. Generally, when the hardness of raw water is high, the dosage is 1~5mg/L.
  • Corrosion inhibition: according to the metal material and corrosion risk to determine the dosage. In general, the dosage is 1~3mg/L.

5.4 Precautions

  • Avoid over dosage: over dosage may lead to water pollution and increase treatment cost.
  • Avoid mixing: do not mix with other chaicals to avoid adverse reactions.
  • Storage conditions: store in a cool, dry and ventilated place, avoid moisture and high taperature.

Summarise

HEDP (Hydroxyethylidene Diphosphonic Acid) is a multifunctional organic phosphonic acid compound with excellent chelating ability and good thermal stability. It is widely used in many fields such as water treatment, industrial cleaning, metal surface treatment, etc. It can effectively prevent scaling, corrosion and disperse suspended particles. The correct use of HEDP can not only improve the treatment effect, but also extend the life of the equipment and reduce maintenance costs. We hope the above information is helpful to you!

HEDP manufacturers

HEDP production facility

TEL:  +86-632-3671188

   FAX: +86-632-3671189

E-mail: export@krchemical.com

   ADD:No.1, Fuqian South Road, Xuecheng Chemical Industrial Park, Xuecheng District, Zaozhuang City, Shandong Province, China

 

Leave a Reply

Your email address will not be published. Required fields are marked *